Liquid reserve systems



Dec. 7, 1965 I R. P. BALLOU 3,221,800

LIQUID RESERVE vSYSTEMS Filed Sept. 7, 1962 T INVENTOR.

United States Patent 3,221,860 LIQUID RESERVE SYSTEMS Richard P. Baliou, Heweil, Mich, assignor to General Motors Corporation, Detroit, Mich, a corporation of Delaware Filed Sept. 7, 1962, Ser. No. 222,111 7 Claims. (Cl. 158-465) This invention relates to liquid supply systems and more particularly to systems for selectively supplying liquids from main or reserve zones in supply tanks.

Various expedients have been employed in automobile vehicles to shift the source of supply of liquid fuel, after a main supply has been used, to a reserve supply as contained in a lower zone of a tank. Such a system is taught in United States Patent 3,031,011, granted April 24, 1962, in the names of J. J. Dawson and A. K. Watt. Prior systems of this type have been primarily of a mechanical nature involving considerable structure which must be installed within the tank.

An object of the present invention is to provide an improved liquid reserve system of simple construction.

A feature of the present invention is a solenoid controlled valve and float arrangement for shifting the source of supply of a suction line from one zone of a supply tank to a reserve supply in that tank.

These and other important features of the invention will now be described in detail in the specification and then pointed out more particularly in the appended claims.

In the drawings:

FIGURE 1 is an elevation view of an automobile fuel tank with a Wall portion removed showing the installation of a system representing one embodiment of the present invention;

FIGURE 2 is an enlarged sectional view of components shown in FIGURE 1, the system parts being located as in operation immediately prior to shifting the source of supply to a reserve or lower zone of a supply tank and portions of the circuitry involved being diagrammatically depicted; and

FIGURE 3 is a diagrammatic view of electrical components and circuits employed.

An automobile fuel tank is shown at 19 and liquid fuel therein is depicted at 12. A conventional suction line leading to the engine is depicted at 14. This line leads from a low zone of the tank and is fitted at its inlet end with a filter device 16. The latter may be of nylon mesh or of some other material and such devices are now available on the market and do not form a part of the present invention.

Inserted in the line 14 and cooperating therewith is a casing 18 so that a flow passage 24? is defined leading from a low zone of the tank 1% to the engine to be served. The

top wall of the casing 18 is extended to define an upper chamber 22 in which is supported a solenoid generally indicated at 24 having a conventional coil 34 and a steel core with end plates 26 and 28. Leads 30 and 32 are connected to the coil 34 of the solenoid. A permanent magnet 39 is movable vertically with relation to the steel core. The magnet 39 is fixed to a stem 38 and the latter is provided with a stop 40. Beneath the stop are located a valve member 44 and a float 46. The head of the valve member 44 is tapered as at 48 to control a port 50 in the lower wall of the casing 18. The valve member 44 has 3,221,3fl9 Patented Dec. 7, 19%5 a reduced intermediate portion 52 which extends downwardly through the port 50 and is fixed rigidly to the float 46. The diameter of the stem 38 beneath the stop 40 is such that the valve member and float may freely move along the stem a predetermined distance. The valve 44 constitutes an adequate stop for the float assembly.

Depending from the bottom side of the casing 18 is an annular rim 54 which is adapted to register with and sealingly engage the top surface of the float 46 as will subsequently appear. The gap between the float 46 and the flange 54 has been exaggerated; it would actually be very small.

FIGURE 3 shows a fuel gage 60 which could be similar to that disclosed in the United States Patent 2,883,623, granted April 21, 1959, in the names of H. R. Hastings and C. A. Haut. This instrument is normally operated by a very small current from a source of power supply such as the battery 62 which is grounded at 64 and connected by an ignition switch 66 to a sending unit generally indicated at 68 and represented by a variable resistance 70 having one end of the latter connected to ground at 72. Such sending units are common and easily operated by a float (not shown in the drawings) to vary the resistance in accordance with the liquid level in the supply tank. The gage 60 is conventionally mounted on the instrument panel of the automobile and is connected to the sending unit 68 by a line 74, the coil 34, line 32 and a line '76. As the current for operating the gage 60 is very small, that current is insufficient to cause any motion of the valve element 44.

In practicing the present invention, the above described wiring is supplemented by a line 80, a resistance 81, and a manually operated and normally open push button switch 82 bypassing the gage 60 and also by a pair of easily operated contacts indicated at 84 to be magnetically actuated so that a relatively heavy and sub-normal current passing through the coil 34 may go through a line 86 to ground at 38. A flexible line 92 connects the junction of lines 32 and 76 with the valve 44 to be effective as a second ground when the valve 44 is seated within the port 5% and after the switch 82 is opened as will subsequently appear.

When the tank 10 is full of liquid fuel, the float 46 will be in its raised position and sealingly engaging the depending flange 54 so that there can be no flow through the port 50. The magnet 39 is held to the core plate 28 by magnetic attraction and the buoyancy of the float. The pump or suction flow to the automobile engine is then conventional as the liquid fuel passes through the filter element 16 and by way of the fluid passage 20 to the carburetor. When the supply of liquid fuel is used to such an extent as to alfect the float 46, the latter will lower sufficiently so that a small quantity of airjust enough to prevent normal suction of gasoline-from the tank 1% will pass under the flange 54 and enter the flow passage 20 and thereby cause the engine to sputter. Somewhat prior to this time, the gasoline was at a higher level so that the very small opening under the flange 54 was fully closed. However, it could be opened for short periods of time by the sloshing of gasoline during vehicle acceleration, deceleration or rounding a curve. Should this occur, there would be a substantial change in gasoline level, such that the float 46 would drop and seat the valve 44 thereby maintaining normal car operation. When the engine does sputter thereby warning that the main fuel supply is gone, the operator will momentarily close the switch 82. Up until this time the current through the coil 34 will have been inadequate to operate the solenoid 22, but with the float lowered the current passing through the switch 82 and the resistance 81 is suflicient to close the contacts 84 and in passing through the coil 34 will effect sufliciently strong solenoid action to lower the valve and the magnet 39 so that the latter is no longer effectively attracted to the end plate 28. Energizing of the coil 34 will cause the core plate 28 and the magnet 39 to repel each other, i.e., the magnet 39 and the valve 44 will lower to close the port 50. The engine sputtering will cease and a second supply or reserve supply of fuel will be available to the engine.

When the tank is replenished with fuel, the float 46 will raise and although the port 50 will be opened, such opening will be ineffective because of the reengagement of the depending flange 54 with the float. Automatic resetting for normal operation is realized because as the tank supply is being replenished, the float 4:) rises and lifts the valve 44. The valve, in turn, pushes the stop 40 upward thereby bringing the magnet 39 close enough to the end plate 28 that it Will be retained in its uppermost position by magnetic attraction.

It will be noted that this reserve system is easily adaptable to the usual sending and receiving gage arrangement using one electrical connection to the tank for, as FIG- URE 3 illustrates, only one line 74 need be directed to the fuel tank. Current normally going through the sending unit 68 is too small to do any work in the tank 19 but with the solenoid assist comprising the contacts 84, is a range of valve opening in which the port 50 and the is a range of valve openuing in which the port 50 and the space between the float 46 and the flange 54 are both open. This range of valve opening or corresponding range of fuel level provides a warning period which, if the warning is unheeded, will terminate in engine stoppage before closure of the valve by gravity action on the float. The purpose of the permanent magnet 39 is to hold up the stem and valve assembly during the warning period when the fuel level is within the aforementioned warning range until the push-button switch 82 is operated. When the solenoid coil 34 is grounded to permit increased energy for closing the valve 44, the resistance 70 is shorted out. The gage 60 is adapted to indicate that the reserve supply of fuel is being used. This is done over the same single sender wire 74. When the ground connection to 18 is established shorting out the remaining resistance of the sending unit 68, the pointer on the gage 60 will swing to its extreme end or reserve position. A conventional l-wire or 2-wire gas gage tank sending unit 68 could be quickly burned out by the inadvertent connection of the gage 60 directly to the battery 62 but the present circuit inherently protects the resistance 70 from burnout by two ground connectionsone to initiate solenoid action and the other being supplementary protection for the resistance 70 against burnout.

Protection is aflorded against premature release of the reserve fuel supply, either intentionally or accidentally, by two independent features. The first is the buoyancy of the float 46 for, if it were prematurely released, it would immediately reseat. The second is the limitation imposed on the current through the solenoid even with switch 82 closed. This limitation is due to the magnitude of the resistance 70 at high level conditions. This effect is more marked when the solenoid assist (through contacts 84) is not used, but when the latter is used, it is only necessary that the contacts 84 be tensioned so that they do not close until a current flows corresponding to a certain low value of resistance 70.

I claim:

1. A liquid reserve system including a supply tank, a suction line extending into said tank and having its inlet end portion extending downwardly and terminating within the tank and near the bottom thereof, a control unit including a float arrangement located within said tank, a casing defining an upper chamber and a flow passage in communication with said suction line and said upper chamber, a permanent magnet and a solenoid mounted in said upper chamber, a bottom portion of said solenoid being electromagnetic, a port in said casing, a valve element having a reduced portion extending through said port and fixed to said float arrangement for movement with the latter and a head adapted to seat within said casing and close said port, a stem slidable in said valve element with its upper end fixed to said magnet to move vertically therewith, a stop on said stem determining an extent of relative motion of said stem and said valve element, an outer portion of said casing surrounding said port, said float arrangement being spaced from said casing when said valve element is positioned to close said port and being adapted to seat on said outer casing portion when said valve element is raised from said port, means for energizing said solenoid, and said magnet and solenoid bottom portion being in facing relation.

2. A liquid reserve system including a supply tank, a suction line extending into said tank and having one end portion terminating adjacent the bottom interior surface of said tank, a casing cooperating with said suction line in defining a flow passage, a solenoid and permanent magnet mounted in said casing, a port in said casing, a valve element and float arrangement coaxial with said port and connected for joint movement, said valve arrangement being positioned to control said port, a seat on said casing and surrounding said port, said valve arrangement being in registry with said seat and adapted to contact the latter as a seal, a stern slidable in said valve element and connected to said magnet to move therewith, a stop on said stem determining an extent of relative movement of said magnet and float, said float arrangement being spaced from said casing when said valve element is positioned to close said port and being adapted to seat on said casing when said port is opened, means for energizing said sole noid, and said magnet being positioned to be epelled by said solenoid when the latter is energized.

3. A liquid reserve system including a tank, a suction line leading from a low interior zone of said tank, a casing in said tank and connected into said line and enclosing a solenoid and a permanent magnet, a port in a bottom wall of said casing, a valve and float arrangement controlling said port, a control circuit including a power source, a switch connecting the latter to said solenoid and to ground, and the arrangement being such that closure of said switch repels said magnet to close said port and a rising movement of said float is adapted to effect closure of said port.

4. A liquid reserve system including a suction line leading downwardly into a liquid supply and having a low main opening and a high reserve opening therein, a float valve arrangement disposed to close said high reserve opening by buoyant action during normal liquid level and to tend to open said high reserve opening by gravitational action during low liquid level, and electrical means for closing said high reserve opening when said gravitational action becomes effective.

5. A liquid reserve system including a suction line leading downwardly into a tank containing a supply of liquid such as liquid fuel and having a low and a high opening communicating with said tank, a float valve arrangement disposed to close said high opening during normal liquid level and tend to open said high opening during low liquid level, a gage and single wire sender unit for measuring said supply, and electromagnetic means operable over said wire for closing said high opening when said float valve arrangement becomes effective at attainment of low liquid level.

6. A liquid reserve system including a suction line leading downwardly into a liquid supply tank, said suction line having a high opening and a low opening, a float valve arrangement controlling said high opening, a gage 5 and a sender unit connected by a single Wire for measuring the liquid level in said tank, and electromagnetic means controllable by said single Wire for closing said high opening with said float valve arrangement by momentary energization when said level is low.

7. A liquid reserve system as set forth in claim 6 in which said sender unit at high liquid level has a magnitude of resistance at high liquid level to render said electromagnetic means ineifective in positioning said float valve arrangement.

References Cited by the Examiner UNITED STATES PATENTS 2/1922 Muzzy 15846.5 8/1938 Gould 158-465 FREDERICK KE'ITERER, JAMES W. WESTHAVER,

Examiners.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,221,800 December 7, 1965 Richard P. Ballou It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

Column 3, line 31, after "84," insert the valve 44 is positively and strongly operated. There lines 32 and 33, strike out "and the is a range of valve openuing in which the port 50".

Signed and sealed this 13th day of December 1966.

( Awest:

ERNEST W. SWIDER Attesting Officer EDWARD J. BRENNER Commissioner of Patents 

1. A LIQUID RESERVE SYSTEM INCLUDING A SUPPLY TANK, A SUCTION LINE EXTENDING INTO SAID TANK AND HAVING ITS INLET END PORTION EXTENDING DOWNWARDLY AND TERMINATING WITHIN THE TANK AND NEAR THE BOTTOM THEREOF, A CONTROL UNIT INCLUDING A FLOAT ARRANGEMENT LOCATED WITHIN SAID TANK, A CASING DEFINING AN UPPER CHAMBER AND A FLOW PASSAGE IN COMMUNICATION WITH SAID SUCTION LINE AND SAID UPPER CHAMBER, A PERMANENT MAGNET AND A SOLENOID MOUNTED IN SAID UPPER CHAMBER, A BOTTOM PORTION OF SAID SOLENOID BEING ELECTROMAGNETIC, A PORT IN SAID CASING, A VALVE ELEMENT HAVING A REDUCED PORTION EXTENDING THROUGH SAID PORT AND FIXED TO SAID FLOAT ARRANGEMENT FOR MOVEMENT WITH THE LATTER AND A HEAD ADAPTED TO SEAT WITHIN SAID CASING AND CLOSED SAID PORT, A STEM SLIDABLE IN SAID VALVE ELEMENT WITH ITS UPPER END FIXED TO SAID MAGNET TO MOVE VERTICALLY THEREWITH, A STOP ON SAID STEM DETERMINING 